package com.teddytailor.research.ocr;

import java.awt.Component;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.ColorModel;
import java.awt.image.MemoryImageSource;
import java.awt.image.PixelGrabber;
import java.io.File;

import javax.imageio.ImageIO;

import com.teddytailor.research.ocr.util.ImageFrame;
import com.teddytailor.research.ocr.util.ImageFrame.ImageProcessHandler;

public class EdgeDetector extends Component {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	final float ORIENT_SCALE = 40F;
	private int height;
	private int width;
	private int picsize;
	private int data[];
	private int derivative_mag[];
	private int magnitude[];
	private int orientation[];
	private Image sourceImage;
	private Image edgeImage;
	private int threshold1;
	private int threshold2;
	private int threshold;
	private int widGaussianKernel;
	
	
	public static void main(String[] args) throws Exception{
		new ImageFrame(new ImageProcessHandler() {
			@Override
			public Image process(File f) throws Exception {
				EdgeDetector edgeDetector=new EdgeDetector();
		        edgeDetector.setSourceImage(ImageIO.read(f));
		        edgeDetector.setThreshold(128);
		        edgeDetector.setWidGaussianKernel(5);
		        try {
		            edgeDetector.process();
		        }
		        catch(EdgeDetectorException e) {
		            System.out.println(e.getMessage());
		        }
		        return edgeDetector.getEdgeImage();
			}
		});
        
	}
	

	public EdgeDetector() {
		threshold1 = 50;
		threshold2 = 230;
		setThreshold(128);
		setWidGaussianKernel(15);
	}

	public void process() throws EdgeDetectorException {
		if (threshold < 0 || threshold > 255)
			throw new EdgeDetectorException("The value of the threshold is out of its valid range.");
		if (widGaussianKernel < 3 || widGaussianKernel > 40)
			throw new EdgeDetectorException("The value of the widGaussianKernel is out of its valid range.");
		width = sourceImage.getWidth(this);
		height = sourceImage.getHeight(this);
		picsize = width * height;
		data = new int[picsize];
		magnitude = new int[picsize];
		orientation = new int[picsize];
		float f = 1.0F;
		canny_core(f, widGaussianKernel);
		thresholding_tracker(threshold1, threshold2);
		for (int i = 0; i < picsize; i++)
			if (data[i] > threshold)
				data[i] = 0xff000000;
			else
				data[i] = -1;

		edgeImage = pixels2image(data);
		data = null;
		magnitude = null;
		orientation = null;
	}

	private void canny_core(float f, int i) {
//		boolean flag = false;
//		boolean flag1 = false;
		derivative_mag = new int[picsize];
		float af4[] = new float[i];
		float af5[] = new float[i];
		float af6[] = new float[i];
		data = image2pixels(sourceImage);
		int k4 = 0;
		do {
			if (k4 >= i)
				break;
			float f1 = gaussian(k4, f);
			if (f1 <= 0.005F && k4 >= 2)
				break;
			float f2 = gaussian((float) k4 - 0.5F, f);
			float f3 = gaussian((float) k4 + 0.5F, f);
			float f4 = gaussian(k4, f * 0.5F);
			af4[k4] = (f1 + f2 + f3) / 3F / (6.283185F * f * f);
			af5[k4] = f3 - f2;
			af6[k4] = 1.6F * f4 - f1;
			k4++;
		} while (true);
		int j = k4;
		float af[] = new float[picsize];
		float af1[] = new float[picsize];
		int j1 = width - (j - 1);
		int l = width * (j - 1);
		int i1 = width * (height - (j - 1));
		for (int l4 = j - 1; l4 < j1; l4++) {
			for (int l5 = l; l5 < i1; l5 += width) {
				int k1 = l4 + l5;
				float f8 = (float) data[k1] * af4[0];
				float f10 = f8;
				int l6 = 1;
				int k7 = k1 - width;
				for (int i8 = k1 + width; l6 < j; i8 += width) {
					f8 += af4[l6] * (float) (data[k7] + data[i8]);
					f10 += af4[l6] * (float) (data[k1 - l6] + data[k1 + l6]);
					l6++;
					k7 -= width;
				}

				af[k1] = f8;
				af1[k1] = f10;
			}

		}

		float af2[] = new float[picsize];
		for (int i5 = j - 1; i5 < j1; i5++) {
			for (int i6 = l; i6 < i1; i6 += width) {
				float f9 = 0.0F;
				int l1 = i5 + i6;
				for (int i7 = 1; i7 < j; i7++)
					f9 += af5[i7] * (af[l1 - i7] - af[l1 + i7]);

				af2[l1] = f9;
			}

		}

		af = null;
		float af3[] = new float[picsize];
		for (int j5 = k4; j5 < width - k4; j5++) {
			for (int j6 = l; j6 < i1; j6 += width) {
				float f11 = 0.0F;
				int i2 = j5 + j6;
				int j7 = 1;
				for (int l7 = width; j7 < j; l7 += width) {
					f11 += af5[j7] * (af1[i2 - l7] - af1[i2 + l7]);
					j7++;
				}

				af3[i2] = f11;
			}

		}

		af1 = null;
		j1 = width - j;
		l = width * j;
		i1 = width * (height - j);
		for (int k5 = j; k5 < j1; k5++) {
			for (int k6 = l; k6 < i1; k6 += width) {
				int j2 = k5 + k6;
				int k2 = j2 - width;
				int l2 = j2 + width;
				int i3 = j2 - 1;
				int j3 = j2 + 1;
				int k3 = k2 - 1;
				int l3 = k2 + 1;
				int i4 = l2 - 1;
				int j4 = l2 + 1;
				float f6 = af2[j2];
				float f7 = af3[j2];
				float f12 = hypotenuse(f6, f7);
				int k = (int) ((double) f12 * 20D);
				derivative_mag[j2] = k >= 256 ? 255 : k;
				float f13 = hypotenuse(af2[k2], af3[k2]);
				float f14 = hypotenuse(af2[l2], af3[l2]);
				float f15 = hypotenuse(af2[i3], af3[i3]);
				float f16 = hypotenuse(af2[j3], af3[j3]);
				float f18 = hypotenuse(af2[l3], af3[l3]);
				float f20 = hypotenuse(af2[j4], af3[j4]);
				float f19 = hypotenuse(af2[i4], af3[i4]);
				float f17 = hypotenuse(af2[k3], af3[k3]);
				float f5;
				if (f6 * f7 <= (float) 0 ? Math.abs(f6) >= Math.abs(f7) ? (f5 = Math.abs(f6 * f12)) >= Math.abs(f7 * f18 - (f6 + f7) * f16)
						&& f5 > Math.abs(f7 * f19 - (f6 + f7) * f15) : (f5 = Math.abs(f7 * f12)) >= Math.abs(f6 * f18 - (f7 + f6) * f13)
						&& f5 > Math.abs(f6 * f19 - (f7 + f6) * f14) : Math.abs(f6) >= Math.abs(f7) ? (f5 = Math.abs(f6 * f12)) >= Math.abs(f7 * f20
						+ (f6 - f7) * f16)
						&& f5 > Math.abs(f7 * f17 + (f6 - f7) * f15) : (f5 = Math.abs(f7 * f12)) >= Math.abs(f6 * f20 + (f7 - f6) * f14)
						&& f5 > Math.abs(f6 * f17 + (f7 - f6) * f13)) {
					magnitude[j2] = derivative_mag[j2];
					orientation[j2] = (int) (Math.atan2(f7, f6) * (double) 40F);
				}
			}

		}

		derivative_mag = null;
		af2 = null;
		af3 = null;
	}

	private float hypotenuse(float f, float f1) {
		if (f == 0.0F && f1 == 0.0F)
			return 0.0F;
		else
			return (float) Math.sqrt(f * f + f1 * f1);
	}

	private float gaussian(float f, float f1) {
		return (float) Math.exp((-f * f) / ((float) 2 * f1 * f1));
	}

	private void thresholding_tracker(int i, int j) {
		for (int k = 0; k < picsize; k++)
			data[k] = 0;

		for (int l = 0; l < width; l++) {
			for (int i1 = 0; i1 < height; i1++)
				if (magnitude[l + width * i1] >= i)
					follow(l, i1, j);

		}

	}

	private boolean follow(int i, int j, int k) {
		int j1 = i + 1;
		int k1 = i - 1;
		int l1 = j + 1;
		int i2 = j - 1;
		int j2 = i + j * width;
		if (l1 >= height)
			l1 = height - 1;
		if (i2 < 0)
			i2 = 0;
		if (j1 >= width)
			j1 = width - 1;
		if (k1 < 0)
			k1 = 0;
		if (data[j2] == 0) {
			data[j2] = magnitude[j2];
			boolean flag = false;
			int l = k1;
			do {
				if (l > j1)
					break;
				int i1 = i2;
				do {
					if (i1 > l1)
						break;
					int k2 = l + i1 * width;
					if ((i1 != j || l != i) && magnitude[k2] >= k && follow(l, i1, k)) {
						flag = true;
						break;
					}
					i1++;
				} while (true);
				if (!flag)
					break;
				l++;
			} while (true);
			return true;
		} else {
			return false;
		}
	}

	private Image pixels2image(int ai[]) {
		MemoryImageSource memoryimagesource = new MemoryImageSource(width, height, ColorModel.getRGBdefault(), ai, 0, width);
		return Toolkit.getDefaultToolkit().createImage(memoryimagesource);
	}

	private int[] image2pixels(Image image) {
		int ai[] = new int[picsize];
		PixelGrabber pixelgrabber = new PixelGrabber(image, 0, 0, width, height, ai, 0, width);
		try {
			pixelgrabber.grabPixels();
		} catch (InterruptedException interruptedexception) {
			interruptedexception.printStackTrace();
		}
		boolean flag = false;
		int k1 = 0;
		do {
			if (k1 >= 16)
				break;
			int i = (ai[k1] & 0xff0000) >> 16;
			int k = (ai[k1] & 0xff00) >> 8;
			int i1 = ai[k1] & 0xff;
			if (i != k || k != i1) {
				flag = true;
				break;
			}
			k1++;
		} while (true);
		if (flag) {
			for (int l1 = 0; l1 < picsize; l1++) {
				int j = (ai[l1] & 0xff0000) >> 16;
				int l = (ai[l1] & 0xff00) >> 8;
				int j1 = ai[l1] & 0xff;
				ai[l1] = (int) (0.29799999999999999D * (double) j + 0.58599999999999997D * (double) l + 0.113D * (double) j1);
			}

		} else {
			for (int i2 = 0; i2 < picsize; i2++)
				ai[i2] = ai[i2] & 0xff;

		}
		return ai;
	}

	public void setSourceImage(Image image) {
		sourceImage = image;
	}

	public Image getEdgeImage() {
		return edgeImage;
	}

	public void setThreshold(int i) {
		threshold = i;
	}

	public void setWidGaussianKernel(int i) {
		widGaussianKernel = i;
	}

	
	public static class EdgeDetectorException extends Exception{

		/**
		 * 
		 */
		private static final long serialVersionUID = 1L;

		public EdgeDetectorException(String message) {
			super(message);
		}
		
	}
}
